1. Johns Hopkins Hospital, Baltimore, Md.
2. Mayo Clinic, Rochester, Minn.
3. Cleveland Clinic, Ohio
4. Massachusetts General Hospital, Boston
5. University of California, Los Angeles Medical Center
6. New York Presbyterian Hospital, New York, N.Y.
7. Duke University Medical Center, Durham, N.C.
8. Barnes-Jewish Hospital, St. Louis, Mo.
9. University of California, San Francisco Medical Center, San Francisco, Calif.
10. University of Washington Medical Center, Seattle, Wash.